Comment fonctionne l'horloge de Notre-Dame-de-Paris #HORLOGENOTREDAME #DENISROEGEL

(english below)

•••• POUR EN SAVOIR PLUS / MORE INFOS @BusinessMontres :
•••• MORE INFO : Paris Notre-Dame clock: animation of the going work (https://bit.ly/3hC7Kpq)

•••• L'ancienne horloge Collin, détruite le 15 avril 2019, a été modélisée en 3D. Il a fallu reconstruire des centaines de pièces.
Ce modèle a été réalisé à partir de relevés et de photographies, il ne prétend pas du tout être une copie parfaite de l'horloge. Il y a inévitablement des zones d'ombres et des simplifications. Le but de ce modèle n'est pas non plus d'être un modèle prêt à usiner. Je n'ai pas la naïveté de croire cela. D'ailleurs, je ne pense pas que ce soit une bonne idée de reconstruire l'horloge et de la remettre dans les combles. Il y a mieux à faire. Ce modèle a bien d'autres intérêts, plus grands que ceux d'une reconstruction, à savoir un intérêt pédagogique, il représente une assistance pour d'autres relevés, et il représente une opération de rétro-ingénierie qui donne un aperçu de la conception, aperçu que de simples mesures transférées sur un logiciel de CAO de donnent pas. Il y a donc un apport à la connaissance de cette horloge, et même de ces horloges.
Ce modèle est aussi utile parce qu'il est basé sur des photographies inédites et parce qu'il peut servir de comparaison avec des horloges comme celle de la Trinité qui ne sont pas totalement identiques à celle de Notre-Dame et qui ne peuvent aveuglément servir de base à une reconstruction fidèle.

•••• Paris Notre-Dame clock: animation of the going work
This is the first animation of the going work of my model of the Paris Notre-Dame clock which was destroyed by fire on April 15, 2019. The model is based on my examination of the clock and is available here: https://sites.google.com/view/horloge... and https://github.com/roegeld/notredame
The animation was made by slightly fine tuning certain parts, in particular the escapement pallets (which are wrong in my online model, but have been fixed here), and the maintaining power pawl (which was a bit too thick). Please also notice that I have used a rigid suspension of the pendulum and that the blade is not flexible. Sometime in the future I might fix that, but I think we can live with it now. (I am also drawing your attention to the fact that the actual pendulum rod is slightly different from the one in my model, and that there are other slight differences, some of which have been corrected in my private working model.)

I currently have no plans to animate the striking works. First, they are pretty straightforward to understand, which is not the case of the going work. Second, several mechanical constraints require a bit more fine tuning than for the going work, and I do not have the time to do it now. Animating the striking works is not too difficult, but getting the mechanical constraints right would take more time. One should realize that whereas it is (relatively) easy to design a mechanism from scratch, or to model a mechanism at hand, it is much more difficult to model faithfully something that does no longer exist, and using only a few measures and photographs.

I am also drawing the attention to two other related projects. First, there is an association in Paris with the aim of modelling the clock of the Trinity church in Paris, which is similar but not identical to that of Notre-Dame (the dimensions are different, as well as the teeth counts, various features differ, and the remontoire mechanism has partly been removed). This association may plan to draw plans of the Notre-Dame clock. This will be difficult, given that the remains of the clock are pretty much unusable, and given that there are some uncertainties in my own work.

The second project is that of the Russian Raketa watch company based in Saint Petersburg. The Paris association (by J.-B. Viot) gave to Raketa my model (which they were entitled to give), and Raketa now seems to use my model to make plans. This is all fine, but Raketa has to be careful that the online model is not the final model of Notre-Dame and that some parts still need to be completed and some dimensions adapted. My initial model (completed in the Spring of 2020) was never meant and made to be animated. I only wanted to make something that looked as close as possible to the original clock. It happens that the going work was almost functional, but the striking works still require some tuning. I am happy to let the Paris association and the Raketa company continue my work.

D. Roegel